Environment & Vegetation Optimization

Challenge

The project’s vegetation and environment setup was outdated and inefficient, leading to performance issues across the scenes. It relied on a combination of Nature Renderer, MicroSplat, and The Vegetation Engine (TVE). However, the systems weren’t properly integrated or optimized:

Trees were manually placed in each neighborhood and lacked instanced batching, causing excessive draw calls.
Grass was incorrectly painted as trees, adding unnecessary complexity to the rendering pipeline.
The environment assets, such as roads and buildings, were high-poly and fragmented into multiple separate meshes —for example, road sections were split into 1x1 chunks instead of being unified into a single mesh.
Overall, the environment was not leveraging Level of Detail (LOD) or impostor systems to reduce geometry complexity at distance.

Solution

To improve performance and streamline the environment pipeline, I implemented the following changes:

Upgraded the vegetation system from The Vegetation Engine to Visual Engine, alongside the latest Nature Renderer. This provided improved support for batching, LODs, and optimized shaders.
Repainted and configured vegetation, ensuring all trees were managed by Nature Renderer’s depth buffer batching system, dramatically improving draw call efficiency for large areas of foliage.
Integrated LODs and impostors for all vegetation assets. Trees and large plants transitioned through multiple LOD levels and, at far distances, were replaced with low-cost impostors, significantly reducing the poly count in each scene.
Migrated from The Vegetation Engine to Visual Engine, gaining finer control over grass shaders and feature usage. By selectively enabling only necessary shader features, I reduced overdraw and shader complexity, improving grass rendering performance without sacrificing visual quality.
Combined fragmented environment meshes into larger, optimized assets:
- Road meshes were merged into unified sections instead of 1x1 chunks.
- Buildings and houses were grouped and optimized to reduce poly counts and improve culling efficiency.
- Other static environment assets were consolidated where appropriate, minimizing draw calls and improving scene organization.

Result

These improvements led to a significant reduction in poly counts and draw calls, improved rendering efficiency, and smoother performance across all neighborhood scenes—while maintaining or enhancing visual fidelity.

Hometopia